Support installing without cert-manager (#834)

* Support installing without cert-manager

README.md

@@ -32,6 +32,7 @@ ToC:
   - [Stateful Runners](#stateful-runners)
   - [Ephemeral Runners](#ephemeral-runners)
   - [Software Installed in the Runner Image](#software-installed-in-the-runner-image)
+  - [Using without cert-manager](#using-without-cert-manager)
   - [Common Errors](#common-errors)
 - [Contributing](#contributing)
 
@@ -43,7 +44,7 @@ ToC:
 
 ## Installation
 
-actions-runner-controller uses [cert-manager](https://cert-manager.io/docs/installation/kubernetes/) for certificate management of Admission Webhook. Make sure you have already installed cert-manager before you install. The installation instructions for cert-manager can be found below.
+By default, actions-runner-controller uses [cert-manager](https://cert-manager.io/docs/installation/kubernetes/) for certificate management of Admission Webhook. Make sure you have already installed cert-manager before you install. The installation instructions for cert-manager can be found below.
 
 - [Installing cert-manager on Kubernetes](https://cert-manager.io/docs/installation/kubernetes/)
 
@@ -1236,6 +1237,35 @@ spec:
   image: YOUR_CUSTOM_DOCKER_IMAGE
 ```
 
+### Using without cert-manager
+
+Assuming you are installing in the default namespace, ensure your certificate has SANs:
+
+* `webhook-service.actions-runner-system.svc`
+* `webhook-service.actions-runner-system.svc.cluster.local`
+
+It is possible to use a self-signed certificate by following a guide like
+[this one](https://mariadb.com/docs/security/encryption/in-transit/create-self-signed-certificates-keys-openssl/)
+using `openssl`.
+
+Install your certificate as a TLS secret:
+
+```shell
+$ kubectl create secret tls webhook-server-cert \
+  -n actions-runner-system \
+  --cert=path/to/cert/file \
+  --key=path/to/key/file
+```
+
+Set the Helm chart values as follows:
+
+```shell
+$ CA_BUNDLE=$(cat path/to/ca.pem | base64)
+$ helm --upgrade install actions-runner-controller/actions-runner-controller \
+  certManagerEnabled=false \
+  admissionWebHooks.caBundle=${CA_BUNDLE}
+```
+
 ### Common Errors
 
 #### invalid header field value

charts/actions-runner-controller/README.md

@@ -97,3 +97,5 @@ All additional docs are kept in the `docs/` folder, this README is solely for do
 | `githubWebhookServer.podDisruptionBudget.enabled`        | Enables a PDB to ensure HA of githubwebhook pods                                                                           |      false                                                           |
 | `githubWebhookServer.podDisruptionBudget.minAvailable`   | Minimum number of pods that must be available after eviction                                                               |                                                                      |
 | `githubWebhookServer.podDisruptionBudget.maxUnavailable` | Maximum number of pods that can be unavailable after eviction. Kubernetes 1.7+ required.                                   |                                                                      |
+| `certManagerEnabled`                                     | Enable cert-manager. If disabled you must set admissionWebHooks.caBundle and create TLS secrets manually                   | true                                                                 |
+| `admissionWebHooks.caBundle`                             | Base64-encoded PEM bundle containing the CA that signed the webhook's serving certificate                                  |                                                                      |

charts/actions-runner-controller/templates/certificate.yaml

@@ -1,3 +1,4 @@
+{{- if .Values.certManagerEnabled }}
 # The following manifests contain a self-signed issuer CR and a certificate CR.
 # More document can be found at https://docs.cert-manager.io
 # WARNING: Targets CertManager 0.11 check https://docs.cert-manager.io/en/latest/tasks/upgrading/index.html for breaking changes
@@ -22,3 +23,4 @@ spec:
     kind: Issuer
     name: {{ include "actions-runner-controller.selfsignedIssuerName" . }}
   secretName: {{ include "actions-runner-controller.servingCertName" . }}
+{{- end }}

charts/actions-runner-controller/templates/webhook_configs.yaml

@@ -5,12 +5,17 @@ kind: MutatingWebhookConfiguration
 metadata:
   creationTimestamp: null
   name: {{ include "actions-runner-controller.fullname" . }}-mutating-webhook-configuration
+  {{- if .Values.certManagerEnabled }}
   annotations:
     cert-manager.io/inject-ca-from: {{ .Release.Namespace }}/{{ include "actions-runner-controller.servingCertName" . }}
+  {{- end }}
 webhooks:
 - admissionReviewVersions:
   - v1beta1
   clientConfig:
+    {{- if .Values.admissionWebHooks.caBundle }}
+    caBundle: {{ quote .Values.admissionWebHooks.caBundle }}
+    {{- end }}
     service:
       name: {{ include "actions-runner-controller.webhookServiceName" . }}
       namespace: {{ .Release.Namespace }}
@@ -31,6 +36,9 @@ webhooks:
 - admissionReviewVersions:
   - v1beta1
   clientConfig:
+    {{- if .Values.admissionWebHooks.caBundle }}
+    caBundle: {{ .Values.admissionWebHooks.caBundle }}
+    {{- end }}
     service:
       name: {{ include "actions-runner-controller.webhookServiceName" . }}
       namespace: {{ .Release.Namespace }}
@@ -51,6 +59,9 @@ webhooks:
 - admissionReviewVersions:
   - v1beta1
   clientConfig:
+    {{- if .Values.admissionWebHooks.caBundle }}
+    caBundle: {{ .Values.admissionWebHooks.caBundle }}
+    {{- end }}
     service:
       name: {{ include "actions-runner-controller.webhookServiceName" . }}
       namespace: {{ .Release.Namespace }}
@@ -71,6 +82,9 @@ webhooks:
 - admissionReviewVersions:
   - v1beta1
   clientConfig:
+    {{- if .Values.admissionWebHooks.caBundle }}
+    caBundle: {{ .Values.admissionWebHooks.caBundle }}
+    {{- end }}
     service:
       name: {{ include "actions-runner-controller.webhookServiceName" . }}
       namespace: {{ .Release.Namespace }}
@@ -96,12 +110,17 @@ kind: ValidatingWebhookConfiguration
 metadata:
   creationTimestamp: null
   name: {{ include "actions-runner-controller.fullname" . }}-validating-webhook-configuration
+  {{- if .Values.certManagerEnabled }}
   annotations:
     cert-manager.io/inject-ca-from: {{ .Release.Namespace }}/{{ include "actions-runner-controller.servingCertName" . }}
+  {{- end }}
 webhooks:
 - admissionReviewVersions:
   - v1beta1
   clientConfig:
+    {{- if .Values.admissionWebHooks.caBundle }}
+    caBundle: {{ .Values.admissionWebHooks.caBundle }}
+    {{- end }}
     service:
       name: {{ include "actions-runner-controller.webhookServiceName" . }}
       namespace: {{ .Release.Namespace }}
@@ -122,6 +141,9 @@ webhooks:
 - admissionReviewVersions:
   - v1beta1
   clientConfig:
+    {{- if .Values.admissionWebHooks.caBundle }}
+    caBundle: {{ .Values.admissionWebHooks.caBundle }}
+    {{- end }}
     service:
       name: {{ include "actions-runner-controller.webhookServiceName" . }}
       namespace: {{ .Release.Namespace }}
@@ -142,6 +164,9 @@ webhooks:
 - admissionReviewVersions:
   - v1beta1
   clientConfig:
+    {{- if .Values.admissionWebHooks.caBundle }}
+    caBundle: {{ .Values.admissionWebHooks.caBundle }}
+    {{- end }}
     service:
       name: {{ include "actions-runner-controller.webhookServiceName" . }}
       namespace: {{ .Release.Namespace }}

charts/actions-runner-controller/values.yaml

@@ -199,3 +199,9 @@ githubWebhookServer:
     enabled: false
     # minAvailable: 1
     # maxUnavailable: 3
+
+certManagerEnabled: true
+
+admissionWebHooks:
+  {}
+  #caBundle: "Ci0tLS0tQk...<base64-encoded PEM bundle containing the CA that signed the webhook's serving certificate>...tLS0K"